Locomotive-boiler.



Farmen Aug. i, |899.

D. DRUMMND. LMUTWE BUILER.

(Appuecinn med Feb. 1a, 189s.)

um man.)

2 Sheets-Sheet L \-\\1\..\\\ n u n m .lill

UNITED STATES PATENT OFFICE.

DUGALD DRUMMOND, OF SRBITON, ENGLAND.

LOCOMOTIVEBOILER,

SPECIFICATION forming part of Letters Patent No. 629,893, datedr Augustv1, 1899".

Application iiled February' 16,1898. Serial No. 670,467. iNo' model.)

To all whom, t may concern:

Be it knownithat I, DUGALD DRUMMOND, engineer, of South Bank Lodge,Surbiton, in the county of Surrey, England, have invented* new anduseful Improvementsin Locomotive-l Boilers, of which the following is aspecification.

This invention, which relates to boilers for locomotives, has for itsobject to enhance the steam-raising capacity of such boilers; and tothat end it consists in the provision of an arrangement of watentubes soconnecting the sides or Walls of the lire-box that a rapid circulationof water around these walls is produced, while a large heating-surfaceis added to the boiler. Y l l The invention is illustrated by theaccom-` panying drawings, in whichf- A Figure l is a longitudinalelevation ofthe tire-box end of a locomotive-boiler, and Fig. 2 is across-sectionA of the same.

As represented in the drawings, the nre-box is of the ordinary shape,but in the sides or walls of the inner shell A orifices are -forrned forthe reception of water-i ubes B, extending across the fire-box and theends of which are Y expanded or otherwise secured in the side walls.These tubes are inclined and are fitted in two. sets-'one set inproximity to the firingdoor G being inclined in one direction and theset behind inclined in the opposite directionto promote circulation ofthe water in the spaces C between the inner and outer shells A and D ofthe dre-box. These watertubes are fully exposed to the heat of thefurnace, which latter may be of the usual type in locomotives andthegases from which may partly circulate among the tubes A on their way tothe fire-tubes H, leading to the smoke- `box, which are secured in thetube-plate l at the rear of the fire-box in the ordinary` way.

Theset of tubes B nearer the v boiler and farther from the fire-box dooris preferably composed of a larger number of tubes than the first set,owing to the fact that the heat Vis greatest toward the rear of thedre-box.

.In order to provide for access to the watertubes for the purpose ofremoving scale or incrustation or otherwise cleaning the tubes andforrepairing or renewing'theln, removable doors E E are tted on the outershell D lat both sides of the nre-box, these doors being seated on andsecured by screw studs or bolts to flange-pieces F, riveted around thedoorways. These doors may be hinged with slotted brackets to allow thedoor to be drawn clear of the studs or bolts and then swung around 'outof the way.

Having now described the invention, what I claim, and desire to securebyLetters Patent, is Y The combination with a boiler having tubes H, anda lire-box, the fire-box having double sides with water-spaces betweenthem, offa Airst set.

In witness whereof I have hereunto set my hand in presence of twowitnesses. y DUGALD DRUMMOND.

Witnesses: Y

CHAs. G. WATT, A JNO. I-IAZELDTNE.

